PTL 1 discloses a system configured to transmit electric power through capacitive coupling.
The power transmission system described in PTL 1 includes: a power transmitting device including a high-frequency high-voltage generator, generating electrodes to define the couple of generator active/passive electrodes; a power receiving device including a high-frequency high-voltage load, and electromotive electrodes to define the load side active/passive pair.
A voltage lower than that applied to the active electrode is applied to the passive electrode among the generating electrodes, and a voltage lower than that applied to the active electrode is applied to the passive electrode among the electromotive electrodes.
The high-frequency voltage used in this system has a frequency ranging from 10 kHz to 10 MHz and a voltage ranging from 100 V to 10 kV. When the frequency of the high-frequency voltage is within this range, the device does not radiate energy in the form of electromagnetic waves, and an electrostatic field is generated in a surrounding medium because the wavelength (lambda) in the surrounding medium is large enough relative to the size D of the device, or D<<(lambda).
FIG. 1 illustrates the basic configuration of the power transmission system of PTL 1. The power transmitting device includes a high-frequency high-voltage generator 1, a passive electrode 2, and an active electrode 3. The power receiving device includes a high-frequency high-voltage load 5, a passive electrode 7, and an active electrode 6. The active electrode 3 of the power transmitting device and the active electrode 6 of the power receiving device are located in proximity to each other and are surrounded by a high electric field area 4 the power transmitting device and the power receiving device are capacitively coupled through the generating and electromotive electrodes and the surrounding dielectric medium.    [PTL 1] National Publication of International Patent Application No. 2009-531009